Cool! It's great that you're interested in writing tales; that's where some of the best character development and worldbuilding we have on the site is.

I see you've got a sandbox, so you're off to a good start! Remember to get your finished words reviewed in the drafts forums and/or the IRC chat. You can also bring an idea to the Ideas and Brainstorming forum before starting a draft, if you want to make sure your concept is solid before you commit to writing the entire article.